Facebook has yet again drawn the ire of conservatives, this time after blocking Republican congressional candidate Elizabeth Heng's campaign ad on the grounds of "shocking, disrespectful or sensational content."

Heng, who is running in California's 16th Congressional District (Fresno area), tweeted that Facebook "rejected" the ad due to clips of dead bodies from the Cambodian genocide.

Heng's parents survived the Cambodian genocide in the the 1970s and subsequently immigrated to the United States.

".@facebook rejected my video because it was 'too shocking' for their platform, referring to the scenes of horrific events my parents survived in Cambodia," Heng tweeted. "Facebook, do you think it's right to censor history?"

The candidate tweeted a picture of the notice she received from Facebook, which states, "we don't allow ads that contain shocking disrepectful or sensational content, including ads that depict violence or threats of violence."

"It's unbelievable that @facebook could have such a blatant disregard for the history that many people, including my own parents, have lived through," Heng said. "I'm sure it is 'shocking' for people to hear about this kind of injustice, but this is reality."

Conservatives have long accused Facebook of being biased against Republicans, and some have stepped up their attacks in recent days after the site removed InfoWars content.

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Media: Cheddar TV

Heng's situation has been extensively covered by conservative outlets including the National Review, Washington Times and Daily Wire.

Heng grew up in Fresno and was elected student body president at Stanford University. She obtained an MBA from Yale, and spent six years working in Washington, D.C. Her time in the nation's capital included stints with congressman Ed Royce and with Mitt Romney's presidential campaign.